Document picker



P 3, 970 F. H. SCHALLER 3,527,457

DOCUMENT PICKER Filed Jan. 2, 1968 2 Sheets-Sheet 1 INVENTOR.

FRANK H. SCHALLER ATTORNEY United States Patent 01 fice 3,527,457 Patented Sept. 8, 1970 U.S. Cl. 271-19 Claims ABSTRACT OF THE DISCLOSURE A card picker arrangement which, in a preferred em bodiment, is adapted to pick cards, singly, from a pack by buckling them away from the stack, i.e. by squeezing (one or both) opposed long edges together with picker knives and then, snapping the card down through a oneway gate constriction onto a nearby (packed registered) wait-station support from whence it may be demand-fed (asynchronously) in serial mode with complete isolation from the pack and picking elements, the gate preferably being defined by opposed diverter (fiexure blade) segments biased against the up-coming card in the pack, these segments preferably having their edges oblique to the adjacent picked edges of the cards.

PROBLEMS, INVENTION FEATURES Those skilled in the art of designing unit-record handling equipment, and especially such machines as punched card readers and the like, are well acquainted with the problems of picking a card from a stack quickly and efficiently without interference from adjacent cards such as frictional drag, snagging or interlocking of (heavilylaced) cards and the like. Arrangements for meeting this problem have been suggested, i.e. mechanisms for so picking a card while isolating it from interference with the rest of the stack, but these have been far too complex (e.g. mechanisms for inserting card-separating devices, for injecting forced-air streams, for joggling the stack, for suctionally-picking cards, etc.). For instance, US. 3,309,080 to Masterson indicates problems and picker structure typical of the prior art. The present invention provides a new, and unusually simple, mechanism for meeting this problem by squeezing the initial card in the stack to buckle it along its long axis and to isolate it from any substantial interference by the stack and render it much easier for serial feeding (that is advancement along its elongate axis). Workers in the art will recognize, of course, that a serial feed is highly desirable in certain circumstances, but is often difficult to implement; for instance, because of the interlock problem (interlocking of heavily-laced cards) which becomes especially serious in this mode. Workers will attest to the gravity of this interlock problem. For instance, the web between adjacent-column holes on a thin punched card is long and quite narrow (.125" x not more than .032); hence it is quite weak. If it tears away, even partially, the remanant can substantially cover a hole and block the reading of it. The interlock problem is, of course, seen when such a web in one card snags against a Web in an adjacent card, as they are slid past one another in the serial direction. Moreover, such interlock problems will likely be with us for some time, given the current standard specifications for punched cards (USAS l X 3.21-1967; U.S. Std. for rectangular holes in punched cards specifying the hole size, location, etc.).

The buckling pick mode of the invention greatly enhances serial feeding, substantially eliminating any risk of interlock or similar problems. This buckling mode of card picking not only reduces serial-feed interference but will be seen as advantageously able to present an let enlarged arcuate card profile to the serial feed means for better registration therewith, etc.

Moreover, a preferred implementation of this invention allows the adoption of familiar machine elements which are outstandingly simple, reliable, and desirable to use; e.g. by adopting opposed sets of (stack-supporting) picker knives (in a three-point support) arranged to be synchronously driven against the card for buckling it, while yet providing a balanced array of picking forces and reducing any attendant stack-vibration, etc.

For certain applications of such buckling pickers, it may appear problematical to synchronize the feed means and buckling means; also, it may often be desired to locate the card advance means (such as conventional feed rolls) as close to the wait-station as possible-thus demanding the picked, buckled card to be flattened out as quickly as possible during its serial advancement for optimum engagement with these feed rolls or the like. For such applications, it has been found preferable to form the wait-station, as a snap-in channel (or one-way gate diverter) through which a buckled card can be snapped onto support rails. This feature of the invention has been found to physically isolate cards in a wait-station even more than usual, while yet keeping them close to the IN-pack (and registered therewith) and also leave them in a fiat, easy to drive, condition-the drive means being thereby rendered entirely independent (asynchronous) of the picking means. Such a wait-station has also been found much more tolerant of up-buckling (buckling up toward the stack rather than away from it, as is typically desired).

Such a buckling picker-mode will be recognized as providing other document-handling advantages, such as affording an exceptionally compressed document-transport path, providing a wait-position for picked documents very close to the input stack (and registered therewith, as opposed to conventionally locating it well away from the stack and downstream) and, where desired, in condition for immediate transport past through a processing station with a minimum of unnecessary transport space. Further, transport compression, etc. may be enhanced and quick tracking (of the document) may be facilitated by disposing document detectors alongside this wait-position, the buckling action being arranged conveniently inject a document edge into the detect-zone sidewise.

Regarding this card buckling action and general feed mode, workers will appreciate that card bow or buckling is a natural result of broadside feeding and has heretofore been regarded as very undesirable and to be avoided. Thus, it is surprising to seen this phenomenon employed purposely in the invention. From the following, workers will appreciate that if a card is stiff enough to buckle properly (cards .007 x 7.375 X 3.25" in size and of about 5#/ 1000 weight are typical) it will buckle to thrust itself Well away from the stack so that there is virtually no change of any web-interlock; yet the card has been effectively separated from the stack with only a tiny translation, and without requiring extensive or unusual picker elements. Workers will appreciate the uniqueness of pickers according to the invention, in that they have no throat in the accepted sense and preferably also include a gate constriction, for instance, thus being relatively immune to deformed cards. This is an extremely important advantage and quite unusual in the card-handling art, since virtually every picker today either uses a throat or needs expensive separating means (such as vacuumatic pickers, which are unduly complex, have interlock problems, etc.).

Thus, it is an object of the invention to solve the aforementioned problems and provide the aforementioned and related features and advantges. A related object is to provide picking means adapted to buckle documents in the course of selecting them. A related object is to provide such means for buckling relatively stiff, rectangular documents about their longitudinal axis, rendering them apt for serial advance to a closely adjacent handling station with no danger of interlock or like obstruction. A further related object is to so buckle such documents both to isolate them from the stack and to render them more apt for serial advancement. Yet another object is to so buckle such documents using opposed picker knives. Still a further object is to synchronously drive such picker knives a short excursion for efi'iciency and minimum vibration. Yet a further object is to select documents from a stack thereof by buckling the foremost document about its elongate axis and then advancing it, serially, away from the stack. A related object is to snap buckled documents through a gate onto isolated wait-station supports. A more particular object is to so buckle and serially feed documents asychronously. Yet a further object is to provide such buckling and feeding in conjunction with the use of a stop guide for limiting the buckling of the documents and guiding its serial feed. Another object is to so buckle-pick a document as to inject it sidewise into a wait-section and into registry with a detect-station.

A further object is to provide a throat-less card picker. Another object is to also provide an isolated wait-station and intermediate one-way gate. Another object is to select cards from a stack and serially feed them by buckling them about their elongate axis, snapping them past a diverter (through a throat constriction of reduced planar cross section), into a wait-station channel, and thereafter advancing them serially along their elongate axis. Still a further object is to provide such a throat using a flexure blade means biased against the foremost card in the stack. Yet another object is to provide such a throat using blades having their guide-edges tapered away from the throat profile (of a buckled card) to prevent catching document edges. Still a further, more particular object is to so buckle punched card documents with opposed picker knives and thereafter snap them through such a flexureblade-defined throat-gated into a wait-station channel, for thereafter so advancing them serially to closely adjacent feed rolls, processing stations, etc. Other objects and features of advantages will become apparent to those skilled in the art upon consideration of the following detailed description of the invention in conjunction with the accompaying claims.

The aforementioned objects and features of advantages are provided according to one embodiment of the invention by supporting an input card stack on three picker knives adapted to longitudinally buckle the formost card at a prescribed pick command and by arranging an array of throat-defining flexure blades with their edges biased against the foremost card in the stack so that the buckled card may fall therepast onto a prescribed isolated wait-station channel; thereafter thrusting the card in the channel serially for presentation to card advancing means.

In the drawings wherein like symbols denote like elements;

FIG. 1 is a highly idealized, schematic isometric of a card stack with picker knives adapted to buckle-pick the foremost card and pusher means for serial feeding a so-picked card to downstream advance and processing means, all being schematically indicated;

FIG. 2 is a side view of the picker elements in FIG. 1 in rest condition, together with associated guide means and pusher means;

FIG. 3 shows the arrangement of FIG. 2 with the picker knives in picking condition, i.e. in the process of laterally buckling a card;

FIG. 4 is a sideview of another, preferred, embodiment, similar to that in FIGS. 2 and 3; however, also ineluding modification features, such as a wait-station channel and flexure-blade gate means;

FIG. 5 is a plan view of the picker, pusher and throat blade elements in FIG. 4, together with optional card strobing means, the latter indicated only schematically;

FIG. 6 is a schematic fragmentary side-elevation of the arrangement in FIG. 4 showing one, representative picker knife and engaged card-edge in buckling condition;

FIG. 7B is a side sectional showing of a novel clamp using opposed flexible tubing elements; while FIG. 7A shows these elements during assembly; and

FIG. 8 is a very schematic side-section of a solenoid picker drive apt for use with the invention.

The related embodiments in FIGS. 1, 2 and 3 will indicate the general sense of the aforementioned buckling mode of picking a punched-card type document from a stack, e.g. so as to serially advance it for processing along a minimum-length path with no interference. Thus, a stack PCD of relatively conventional rectangular punched card documents is indicated in FIG. 1 wherein the foremost (bottom) card BC has been presented operatively adjacent a trio of picker knives P, the knives being adapted to be reciprocatingly thrust in synchronism against a long card-edge, card BC being indicated (in phantom) as buckled by knives P. It will be understood that the general function of knives P is to be reciprocated so as to thrust their knife edges in synchronism against the confronting edge portion to buckle the card (also shown in FIG. 3) and then return to rest position (indicated in FIG. 2), while providing a desirable three-point support for the stack PCD. The means for controlling and driving knives P1, P-2, P-3 are well known in the art and will not be dwelt upon; however, an apt drive arrangement is discussed below and shown in FIG. 8. As will become apparent, this picking mode advantageously enables an array of opposed knives to squeeze opposed card edges (thrusting one, or both together) in a picking operation which is simple to implement and superior in efficiency, enabling the picker drive means to be synchronized and balanced to minimize vibration and alleviate such attendant problem as stackjogging, etc. This buckling-pick feature of the invention will also be seen as deriving other significant advantages. Of course, during the buckling operation, it is assumed that a prescribed weighting body (such as a prescribed minimum number of cards in a stack PCD, preferably with a card weight, which is especially useful for a minimum number of cards) will be present to provide a reference surface resisting the up-buckling of the picked card and urging it down and away from stack PCD.

It will be apparent to those skilled in the art that such a buckling-pick mode is a prime feature of the invention and highly significant. For instane, it presents, at least momentarily, an arcuate card profile (as indicated in FIGS. 1 and 3) to the serial drive (pusher) means, such as the schematically indicated push blade BL (or analogous blades BLA in FIG. 2, BLA in FIG. 3). Blade BL will be understood (as indicated by the arrows) to be selectably thrust against a short edge of a buckled card (BC) being driven by any conventional means, such as the schematically indicated solenoid assembly S, understood as conventionally pivoting BL onto the magnet upon timed application of current through leads LL. US. Pat. 3,315,955 to Schaller et a1. indicates a representative pusher mechanism adaptable for such serial feeding, as well as discussing various refinements for enhancing pusher actuation, damping, etc. In some cases, it will be appreciated that actuation of such a pusher means must be controlled to be synchronous with the momentary buckling condition of the card, to take advantage both of its enlarged buckled profile and of its minimum drag-engagement (e.g. only along its long edges) with the card stack PCD. This synchronization need present no problem since the picking can be relatively slow and the picking signal (e.g. if somewhat delayed) can also initiate actuation of the push blade BL. Alternatively, the picker may rest in card-buckling condition, and keeping a picked card so buckled so that it may be pushed any time (asynchronously); also a separate wait-station may be provided (as below). Of course, such synchronization will be necessary in some embodiments, such as those using a wait-station of the type indicated in FIGS. 4, and 6.

A very advantageous effect of this buckling will be seen as the compression of the required card-transport path; for instance, the push-excursion distance through which blade BL must advance the buckled card BC may be extremely small (eg. about /1" to /2 to drive the card nose through an engagement axis F--F, defined by the nip of a pair of drive rolls R-l, R-2-it being understood that when these rolls are thrust together and rotated, the prescribed advancement of the card to utilization means downstream will be conventionally effected, along the direction of arrow fa). This advantage will be appreciated as allowing workers in the art to locate a processing station (e.g. card-reading axis RDRD) uniquely close to the input stack (e.g. locus of foremost card be), not only compressing the transport path but also greatly abbreviating the delay time between cardpick and processing thereof, thus reducing dead-time until readout beginssomething highly prized in high speed computer systems. To accommodate the close proximity of rolls R1, R-2 (and downstream processing stations) to the buckled-card, and to provide minimum interference of card-bow with the (ordinally fiat) roller-engagement, the engaging width (fr) of rolls R may be minimized, consistent with maintaining lateral card-alignment during transport.

In the schematic sideview of FIG. 2, the picker knives (represented by P-3, P-2) are shown in rest (unactuated, non-picking) condition with their knife edges barely in contact with the long edges of the foremost card (initial card C-1 in stack PCD). Also, according to an improvement feature, a reference guide G is provided, having a prescribed conformingly-curved reference surface GS and adapted to limit the buckling (bow) of a picked card and guide it during pushing, etc. (cardguide engagement is indicated in FIG. 3 for buckled card C-l'). It will also be appreciated that where such a guide surface (or surfaces) are provided to extend along a substantial portion of a buckled card length, they can provide alignment advantages, such as deterring the card from laterally skewing (out of its elongate axis during serial feed). Indeed, with the buckled-card in such a stiffened, bowed condition, as indicated in FIG. 3, the reference surface G-S can provide a very snug, stable guiding plane along which it may be serially advanced (as by blade BL), yet without relying solely upon conventional edge-guiding surfaces which can damage or abrade edges, introduce drag, skew, or the like (especially when card-edges must be loaded against them heavily). Where desired, guide G may include pneumatic hold means (known in the art) to suck and hold the card down on surface GS. The schematic, and somewhat exaggerated, representation in FIG. 3 of the actuated (buckling) condition of the picker knives and the buckling card 0-1 will be understood by those in the art as illustrative (full buckling being indicated in FIG. 4). The pusher may coordinate with such a guide surface in several ways. For instance, an alternate push blade BLA, outlined in phantom in FIG. 2, may have a cross section adapted to fit between guide surface GS and the stack PCD, being long enough to engage the outer card portions. Alternatively, such a blade may be modified, as for blade BLA (in FIG. 3) to have a somewhat larger cross section, with guide surface GS being arranged (e.g. interrupted along the card-length) so as not to intersect the push ing excursion.

Workers in the art will appreciate that a prime advantage of this buckle-pick, serial feed arrangement is that, with a very short picking stroke (especially from opposed picker knives, e.g. in FIG. 8), necessary cardbuckling can be effected over a relatively long distance, and so as to span a particularly large (push blade) cross section, the buckled-profile thus providing a sort of mechanical amplification whereby a short picking stroke produces a relatively large card displacement (and large pusher-engagement area). This displacement, of course, may be controlled according to the length of the picking stroke. Picking mechanisms according to this invention may evidently be quite simple, inexpensive, and yet reliable, using known, reliable components. Such a novel buckling pick-mode may also provide a pickedcard which is advantageously stiffened for a better, more stable and aligned serial feed. It will thus be appreciated that document picking has been taught in a new distinctive manner which unlike conventional throated arrangements does not drive the document through a thickness-cOnstrictiOn (and thus is throatless) and unlike other conventional throatless pickers does not thrust the document along, or against, the stack or require complex pick-up mechanisms (such as a suction arm, etc.).

Regarding the driving of picker knives, workers in the art will understand many suitable arrangements, one such being a solenoid-flexure structure similar to a tuning fork, as illustrated by dual drive DR in FIG. 8. For instance, the natural frequency of this structure may be matched to the feed rate for minimum energy input (one may also use squeeze film damping, such as indicated in the aforementioned patent, to damp oscillations of the picker-mounting flexures against a reference surface and minimize secondary vibrations). One may drive these pickers magnetically (e.g. as DR) or by any like means, either thrusting one long card-edge for buckling; or, preferably, thrusting both edges (in synchronism). Dual drive arrangement DR in FIG. 8 will be understood as acting to pull opposed knives (P-l, P-3 shown) together by attracting magnetic spring-plates (fiexures FA, FA) mounting the knives. Thus, upon application of a pick signal, current will be applied through an exciting coil C to generate flux from the opposed poles of a magnet core Mg and pull the fiexures in toward these. The pickerreturn action may be provided by the inherent restoring resilience of the fiexures FA, FA, or by other known equivalents. Reference stops (ST, ST) may be provided to register the knives in rest condition. Of course, the picker drive may either reciprocate to buckle the card momentarily or to cock it into the buckled condition and hold it so for a controlled period. A dual drive means, like DR, will be understood as advantageously driving the opposed knives at high feed rates, maximizing balance and minimizing vibration, etc. For low speeds, a single action arrangement (i.e. thrusting only one card-edge) should suflice. As a refinement feature, picker knives P may be modified to include guide means for minimizing any possible buckling along the long (picking) cardedges. That is, the local pressure of the picker knives on the thrust-portions of a document edge may cause unintended distortion (bending) along this edge, e.g. with flimsy tissue documents. Provision of guide-edges adjacent the usual knife edge and set-back therefrom (e.g. sufficient to accommodate a minor edge-bending and not interfere with the throat fiexures) can meet this contingency.

WAIT-STATION As indicated above, it may he often preferable, according to another prime feature, to provide such buckling pickers with a wait-station of the type indicated in FIGS. 4, 5 and 6. FIG. 4 is a side elevation of a feed mechanism functionally similar to the showings in FIGS. 1, 2 and 3 and understood as constructed and operating the same except as hereinafter noted. This mechanism includes input hopper means (not shown) for presenting a card stack PCD operatively adjacent a pair of picker knives P2, P3 (also a third knife, etc. if desired) and a pusher blade BLL similar to the preceding embodiments and also includes improvement features comprising waitstation (cf. wait-standards ws, ws) and a gate comprised of throatdefining blades 1, 7" (FIGS. 5, 6 also). Standards ws, ws will be understood as including a pair of opposed wait-rail surfaces wg, wg onto which a buckled card will be understood as inserted, through the flexure-gate, to be received on rails wg, wg in a wait condition (such as indicated by picked card we in phantom). Here, as before, it will be understood that the cards in stack PCD are urged conventionally along a prescribed stacking axis V (preferably, by a card weight) to present a foremost card C1 with its long-edges operatively adjacent the knife edges of the pickers, the latter being (concentionally) somewhat narrower than a card-thickness, clearing the next-adjacent card (C-2) so as not to buckle it, the top surfaces pt of the pickers then sliding under C-2 to then support it, and the stack thereon, during the buckling excursions. Wait-station standards ws, ws serve both to mount the opposed flexures f, f and present a respective pair of rigid card-edge-receiving rails wg, wg' disposed in the machine in :buckled-card-receiving" relation to stack PCD and picker knives P. Surfaces wg, wg' are spaced apart slightly more than a maximum card width D w and comprise a pair of smooth, flat, continuous guide surfaces along which the card may be slid during serial feed (and retained thereon, in prescribed flat, aligned condition relative the downstream advance means, such as rollers iR;1, R-2). Surfaces wg, wg' are also, preferably, beveled down and toward one another so as to trap under-width cards, etc. Standards ws, ws, as aforesaid, mount the array of opposed, throat-defining blades 1 (indicated in FIG. 5 as blades f-l through f-S), these blades being adapted in general to define a gate (or planar throat constriction) of prescribed buckled width 1lw, somewhat less than the width Dw of the normal (flat) card. It will be understood that flexures 7 provide a gate through which a buckled card may unidirectionally pass (this width thus being set in accordance with the buckling excursion of the pickers, etc.). Preferably, the throat-defining edges of blades 1 are tapered away from the reference throat-edge which they are intended to define, as indicated in FIG. 5, for reasons associated with preventing a card from hanging up (i.e. locking its long edge thereon, or scraping, as it passes during buckling) and thus allowing it to snap-in freely to the wait-station and rest upon the guide rails wg, wg' (cf. card BC in FIG. 4).

According to an improvement feature, these throat defining edges comprise flexure blades which divert the buckled card away from the stack PCD. Such is indicated schematically for blades f, f in FIG. 4, which are understood as afi'ixed to a respective wait-station standard w-s, ws (e.g. clamped on) so as to be cantilevered out, and upward, against the foremost card in stack PCD, biasingly (e.g. with their face tips bent against C1 in FIG. 4). Blades 9, I will have a prescribed length so that a typical buckled card (such as BC, FIG. 4 or C-1' in FIG. 6) will clear them and be diverted by them down onto rails wg, wg'; the flexure tips the while sliding along the buckling card to finally snap up to biasingly engage the next adjacent card (such as C-2 in FIG. 6) and thus divert the buckled card. Workers in the art will appreciate the advantages of such a one-way (flexure-blade) gate; e.g. in providing a card-diverting guide along which gravity and the inherent stiffness of the noW-unbuckling card may be directed (e.g. bc, FIG. 4). This blade should be sufficiently thin and flexible so that, when a buckled card (such as BC) thrusts its edges outward along the plane of its neighbor (cf. along card C-l in FIG. 4 when knives P start to retract) and start to open into unbuckled condition, the flexure blade edges will direct it down divertingly and prevent its return to stack PCD. The flexibility of these blades will allow them to maintain continuous (bending) contact with the surfaces of the next-adjacent card, unlike a fixed reference edge, regardless of whether the card bounces somewhat (e.g. following stack jogging, card-warp, etc.). Of course, rigid throat edges may be provided where these advantages are not desired or the flexures are not appropriate, and most of the buckling picker-wait-station benefits still be derived. In certain cases, one may wish to use fixed throat edges together with one or more such flexure blades biased against the stack. It will thus be appreciated that for such a throatless buckling picker as aforedescribed, this feature additionally affords a one-way gate at the buckling locus for diverting buckled cards away from the stack.

Workers in this art will also appreciate that such a gate and wait-station as aforedescribed will advantageously isolate a picked (waiting) card from influence of the stack, the pickers, etc. during serial feed, thus facilitating asynchronous feeding and also allowing disposition of downstream adavnce means and processing stations very close to the buckling locus (the card being also rendered flat and unbuckled at this wait-station). For instance, the long edges of documents are often prone to such irregularities as burrs, tears, notches etc.all constituting a hang-up hazard when advance past discontinuous surfaces like the picker knives. Thus, serial feeding such documents along the smooth continuous guide rails wg, wg' will be preferable to so feeding a kept-buckled card (suchas pushing card C-l in FIG. 3).

Another advantageous effect of so snapping picked cards into a flattened wait-condition is that they may be injected immediately through closely proximate processing stations (e.g. across a sensing zone, such as into the strobing zone indicated in FIGS. 6 and 5 as defined by the light fibers fb-l, flu-2, fb-3 etc.); where otherwise they must first be fiatened usually. Workers in the art will understand that, according to this improvement feature, each such a detecting light fiber (light pipe fb) operates rather conventionally to direct light signals to a prescribed registered detect means D, and operates in conjunction with an associated light source and associated source fibers (fb-1 etc.) registered with a respective detect fiber (e.g. fb-l). Each source fiber fb' conducts light signals (from a source S) to sensitize its respective detect fiber fb, establishing a respective detect-axis therebetwen. Any num ber of such detect-axes (altogether constituting a prescribed sensing zone) may be disposed along the waitstation of FIG. 5 (being ararnged to by-pass blades 1, etc. and to locate along the buckled-periphery, i.e. the zone between Tw and Dw) so as to indicate passage of the trailing card-edge (by means well known in the art and not requiring discussion). Other analogous means may be employed to establish such sensing zones into which buckled cards may be so easily injected according to the invention. It will be recognized as another advantage of such a buckling-pick mode that it uniquely affords such a lateral sensing zone (buckling cards into it) and such resultant compression of the required transport path.

Pusher blade BL (FIGS. 1, 5) may, of course, comprise a magnetic flexure blade armature adapted to be attracted against solenoid magnet S, being pivoted from a pin, a clamp or like fixture. One such fixture, especially suitable for clamping a pivotable flexure plate is indicated in FIG. 7B as clamping flexure plate 7-F between two opposed pairs of tubes (7-T/7-TT and 7-T/7-TT') held in blocks B1, B-2. These tubes will be understood as each comprising radially-compressed flexible tubing, such as of a hard elastomer, or a spring metal, etc., according to this feature. It will be understood that such a flexure-tube clamp may be advantageously fabricated, as indicated in FIG. 7A, by providing two sets of like tube sections, cutting out seating grooves 7g, etc. in each block (B-l, B-Z) to receive a respective one of the tubes and then assembling both with the flexure plate 7-F therebetween and opposed tubes pressed in registry so that a prescribed block/ plate static gap g-c is established. Pressing these blocks together sufficiently (force arrows) will reduce this gap to a prescribed dynamic gap value g-a (g-b similar), given a certain stiffness in the tubes (as indicated in 7-B, tube distortion being somewhat exaggerated). The seating-depth of grooves 7-g etc. may be controlled quite simply by cutting a V-notch to a prescribed depth, as indicated, with its angular divergence (D) corresponding to the tube diameter and the depth required to establish gap g-c. As a result, workers will appreciate that plate 7-F is firmly clamped for fiexure-pivoting over a wide are (such as between arc-extremes 7-P, 7 FIG. 7B) without interference from the clamp blocks the while. Virtually any practical pivot-arc (7-A) may be accommodated (according to the value of gap g-b, etc.); whereas heretofore, this has been a severely limiting feature of flexure-plate clamps and has required fussy edgeshaping. Moreover, the pivoting sweep of plate 7-F will produce a stress on fiexure-tubes 7-T etc. such as to simulate a rolling-fiexure action therewith; vastly superior to the typical abrading and discontinuous stressing of such a plate in prior art clamps (e.g. see aforementioned patent).

In summary, it will be apparent to those skilled in the art that a novel, advantageous arrangement has been taught for picking punched cards, or like documents, by buckling them, and especially where, subsequent to such buckling, the cards are snapped-through a one-way gate onto support-rails in a wait-station. Moreover, it will be apparent that while the foregoing embodiments have been provided to clearly teach the pninciples of the inven tion and how they may be implemented, various other equivalent implementations may be used within contemplation of the present claims. For instance, the picker knives may be adapted as known in the art to comprise picking friction rolls, picker wheels, or the like (rather than knives), for instance, such rolls operating to similarly squeeze card-edges together to buckle them. Of course, other buckling modes may be contemplated (e.g. up from a stack, rather than down, where permissible). It will also be apparent that the principles of the invention may be applied to other, analogous document selection apparatus, whether it be operated with a mechanical picker knife and hopper, or with other types of documentinjection systems. It will further be apparent that the invention can provide any such picker apparatus with a throat-less design, dispensing with prior throating or pick-up arrangements and eliminating the typical attendant risks of throat jams, card damage, machine maintenance or the like. The documents may be other than punched cards, of course, comprising any unit records having the problems and characteristics of the type aforementioned. Various means may also be contemplated for assisting in the indicated desired mode of picking (e.g. buckle-and-serial feed), such as gas jet means arranged to assist and accelerate the unbuckling action of the buckled card, etc.

While in accordance with the provision of the statutes there have been illustrated and described the best forms of the invention known, it Will be apparent to those skilled in the art that changes may be made in the forms of the apparatus disclosed without departing from the spirit of the invention as set forth in the appended claims and that in some cases, certain features of the invention may be used to advantage without a corresponding use of other features.

Having now described the invention, what is claimed as new and desired to secure by Letters Patent is:

1. In a document handling apparatus wherein documents are intended to be selected singly from a stack thereof for individual manipulation, a buckling picker having picker means adapted to engage a picked document along opposed parallel edges thereof; said picker means comprising a pair of picker knives adapted to engage an elongate one of said parallel document edges and a third picker knife adapted to contemporaneously engage the opposite document edge in symmetrical synchronism, the three knives also being adapted to support the document stack; stop means in proximity to said picked document; said picker means operative to squeeze one of said opposed parallel edges to so buckle the intermediate document profile so as to be engageable by manipulating means whereat said stop means is adapted to arrest said document and facilitate manipulation; and pusher means adapted to serially feed said picked document subsequent to said buckling.

2. The combination as recited in claim 1 wherein said knives are driven by a balanced dual-feed system.

3. The combination as recited in claim 1 wherein said feed drive comprises selectively operable solenoid means and wherein said knives are mounted on magnetizable fiexure strip means arranged in operative relationship with said solenoid feed to be magnetically pivoted and translated thereby so as to drive said picker knives to squeeze said opposed document edges for buckling, being also so mounted as to provide a self-returning action for returning the knives to non-buckling rest condition.

4. In a document handling apparatus comprising a document manipulating apparatus; a magazine for holding a stack of documents; buckling picker means for thrusting opposed edges of the foremost document of said stack to buckle the intermediate portion of said document away from said stack; stop means disposed centrally of said opposed edges and in proximity to said document to limit the buckling action thereof; and pusher means arranged to transport said document in a direction along its buckling axis, subsequent to said buckling.

5. The combination as recited in claim 4 wherein said pusher means operation is responsive to a feed command and asynchronous of the operation of said buckling picker means.

6. In a document handling apparatus wherein documents are intended to be selected singly from a stack thereof for individual manipulation, a buckling picker means adapted to thrust one or both of opposed parallel document edges toward the other edge to so buckle the intermediate document profile as to be engageable by manipulating means; said manipulating means further comprising serial feed means adapted to so engage a buckled document as to thrust it along the axis of buckling responsive to a respective feed command; said picker means being throat-less and including unidirectional gate means for diverting the buckled document away from the stack thereof and into a fiat, unbuckled condition; and wait-station means adapted to receive the unbuckled document after passage through said gate means.

7. The combination as recited in claim 6 wherein said gate means is adapted to divert a buckled document away from the document stack and to retain the following document in the stack.

8. The combination as recited in claim 7 wherein said gate means comprises a flexure tip biased against the fore most document in the said stack so as to allow said buckling thereof only away from the stack, preventing return of a so-buckled document and directing it away from the stack.

9. The combination as recited in claim 8 wherein said gate means comprise flexure blades disposed so as to define a planar throat-like constriction without interference with the operation of said buckling picker means.

10. The combination as recited in claim 9 wherein the tips of said blades are bent biasingly against the foremost stacked document and, moreover, are irregular in their longitudinal conformation so as to be other than parallel with passing document edges and avoid obstructive engagement therewith.

11. In a document handling apparatus wherein documents are intended to be selected singly from a stack thereof for individual manipulation, a buckling picker means adapted to thrust one or both of opposed parallel document edges toward the other edge to so buckle the intermediate document profile as to be engageable by manipulating means; a wait-station means disposed operatively adjacent the locus of said buckling while being isolated from the said stack and picker means, and wherein is also included pusher means, as said manipulating means adapted to engage said documents on said waitstation means and serially transport them on-demand, asynchronous of the picker means.

12. The combination as recited in claim 11 wherein said wait-station is adapted to include support means adapted to receive said document in fiat, unbuckled condition and serve as a support across which the document may be transported by said pusher means.

13. The combination as recited in claim 11 wherein is also included a detect zone operatively adjacent said Wait-station and adapted to be intersected by said unbuckling document thereat for detection of document presence, condition, and the like.

14. The combination as recited in claim 13 wherein said detection zone comprises a strobe cell array adapted to detect the passage of the trailing document edge during said serial feed.

15. In a document handling apparatus comprising a document manipulating apparatus; a magazine for holding a stack of documents; buckling picker means for thrusting opposed edges of the foremost document of said stack to buckle the intermediate portion of said document away from said stack; stop means in proximity to said buckled document, said stop means arresting said document; and pusher means arranged to transport said document subsequent to buckling, in a direction along its buckling axis responsive to a feed command and asynchronous of the operation of said buckling picker means.

References Cited UNITED STATES PATENTS 1,242,520 10/1917 Cameron 27123 3,395,912 8/1968 Tappolet 271-23 EDWARD A. SROKA, Primary Examiner US. 01. X.R. 221-36, 236 

